Fuel Cells Bulletin 9 electrolyzer was presented at the recent Hannover Fair.
To enable the metal hydride storage units to be filled quickly, Fraunhofer ISE's hydrogen technologists have combined 15 electrolysis cells to form a stack. The individual cells are made from a special plastic using an injection molding process suitable for series production. This reduces the costs for the bipolar plates by around 90%, and the weight of the electrolysis stack is halved.
To fill the metal hydride storage, the hydrogen is supplied at a pressure of 10 bar and dried maintenance-free in a membrane module. A second, downstream drying stage increases the service life by a factor of eight. A microcontrollerbased control concept, which has also been developed at Fraunhofer ISE, ensures that the system operates reliably at the push of a button. A comprehensive safety analysis underlies the system's hardware component-based safety strategy.
As well as the mini electrolyzer, the institute presented its latest work on fuel cell development. 'We are currently expanding the field of application of our micro fuel cells to extreme temperature ranges and thus making them suitable for outdoor use,' explains Dr Christopher Hebling, head of the energy technology department at Fraunhofer ISE. Whether with icy temperatures of -20°C or a heat wave of 40°C, the micro fuel cell system always starts.
The miniaturization of the electrolyzing system and the micro fuel cell system for outdoor applications has been supported by the German federal ministry of economics and technology, and conducted in collaboration with industrial and research partners.